Artificial-tooth crown and securing means therefor



. E.M FEEDER v ARTIFICIAL TOOTH CROWN AND SEC MEANS THEREFOR.

APPLICATION FILED NOV 10. "H9.

' Patented May'30,1922.

siren ENOCH FL EREDEEICKS,

rarer or orrrcaeo, rLLrnoIs, assrcrnon T0 JOY roo rrr COMPANY,

or onrcaeo, runners, a CORPORATION or ILLINOIS.

Specification of Letters Patent.

llatentet'l May 3Q, 1922.

Application filed November 10, 1919. Serial No. 336,905.

To all whom it may concern:

Be it known that I, Finoon M. Fnnnnnrcns, a citizen of the United States, residing at Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvements in an Artificial-Tooth Crown and Securing Means Therefor, of which the following is a specification.

My present invention relates to improvements in artificial tooth crowns and means for securing the same of a type somewhat similar to that disclosed in Letters Patent of the United States, Number 900,363, issued to me on October 6, 1908, and has for one of its objects to greatly improve the construction and etficiency of tooth crowns made according to my aforesaid Letters Patent, and to economize in the amount of certain material used in the construction of the tooth crown and securing means set forth in said Letters Patent, without diminishingits strength or efliciency, and without an increase in the amount of labor and time expended in fitting the crown to or mounting it upon the root of the tooth.

Further objects and advantages of the invention are similar to those set forth in my aforesaid Letters Patent and are as follows:

To provide an artificial tooth crown, more especially for the molar or bicuspid type, which shall be of such construction or shape that it may be readily prepared to accurately fit the backing and solder-base, and in some instances, the exposed end of the natural root with a minimum of grinding or cutting away of parts. ,7

Another object is to provide simple and efficient means for securing the crown firmly in place onthe backing and solder-base and in some cases for securing the crown directly and firmly to the root, and in either case, in such a manner that in the event of breakage of the crown, it will be unnecessary to remove the crown-post in order to place a new crown thereon.

A further object is to provide means whereby the. soldering necessary in securing the crown and parts together may be accomplished without injury to or discoloration of the crown. v

Other objects and advantages of the invention will be disclosed in the sub-joined description and explanation.

The invention consists in certain peculiarities of the construction, novel arrangement. combination and operation of the various parts thereof, as will be hereinafter more fully set forth and specifically claimed, and in order to enable'others skilled in the art to which my invention pertains to make and use the same, I will now proceed to describe it, referring to the accompanying drawing, which serves to illustrate an embodiment of my present improvements, and in which drawing the views are greatly eX- aggerated.

Fig. l of the drawing is a sectional view of a tooth crown provided with fastening means arranged and constructed according to mv present invention, showing it secured to the backing and solder-base and the latter to a portion of the natural root of a molar tooth. Fig. 2 is a longitudinal sectional view of a portion of the crown-post or pin.

Fig. 3 is a cross-sectional view thereof,

' taken on line of Fig. 2 looking in the direction indicated by the arrows.

- Fig. 4- is a detached plan view of the metallic band used in the cavity of the tooth crown for a bearing or support for the crownpost.

Fig. 5 is a transverse sectional view thereof taken on line 55 of Fig. 4 looking in the direction indicated by the arrows.

, Fig. Gis a detached perspective viewof a form of a tooth crown similar to that shown in Fig. 1 illustrating the metallic band located in the upper end of the cavity of said crown, and illustrating the same applied to a front tooth, and

Fig. 7 is a similar view of a tooth crown showing a modification in its construction.

Like numerals of reference refer to corresponding parts throughout the different views of the drawing.

The reference numeral 7 designates a portion of the root of a natural tooth, in the cavity of'which is secured by means of cement S or otherwise, a post 9, which I will term the solder-post and is used in connection with the gold backing. 10 secured on the exposed end of the root to secure the solder-base 11 to the root. i

As shown in Fig. 1 of the drawing, the solder-post 9 projects through the backing l0 and into the solder-base 11 and thus firmly secures said parts together as well as to the root.

The numeral 12 designates, as a whole, the artificial crown which may be made of any suitable shape and size in accordance with the position in which it is to be placed, and is preferably formed of porcelain, but may be made of other suitable material. When made of the molar or bicuspid type, the

crown 12 has extending therefrom a shank or flange 14L,which in cross-section is of very much less size or area than the crown portion 13, so that in fitting the crown to the solder-base, or when desired, to the root, it will be necessary to cut away or grind off the shank or flange only to the desired point, thus saving much time and labor.

Moldedin the usual manner, or in the preferred Way, in the crown 12 is a supporting or hearing band 15 which is preferably made of, platinum, but may be of any other refractory metal. As shown, this band is substantially circular in shape but is provided with diametrically opposed and outwardly extended bosses or protuberanccs 16 produced by stamping or otherwise forming in the inner surface of that portion .of the band 15 where the'bosses 16 are located, vertically disposed grooves 17 which grooves extend through the upper and lower edges of the band, as will be clearly understood by reference to Figs. 1, 1- and'5 of the drawing. This band is located in the upper or outer end of the cavity 18' of the tooth crown which cavity is tapered or enlarged towards its bottom;

While I have shown the band 15 provided with a pair of opposed bosses 16 located diametrically opposite each other and each equipped on its inner surface with a groove 17, yet I desire it to be understood that the band may be providedwith one or more of the grooves and the resultant bosses or protuberances and that they may be arranged diametrically opposite each other or other-. wise. Located within the band 15 is'o ne end of the crown securing post 18 the opposite end portion of which is adapted to be inserted and secured in any desired manner in thesolder-base. The portion of that part of.the post 18 located within the tooth crown 12.is formed with a tapered part 19 corre sponding with the tapered cavity 18 of the tooth crown yet smaller in size so as to leave a space surrounding the same between it and the tapered wall of the cavity 18' as will be readily understood by reference to Fig. 1 ofthe drawing, in which view it will be observed that the tapered part 19 of said post has its larger portion at its free end to rest on or to lie in close proximity to the base of the cavity, in the crown. To form this tapered portion 19 the post 18 is reduced thus forming an annular shoulder 20 at the smaller end of the tapered'part 19, which shoulder as shown in Fig. 1 is located some distance fromthe front outer or upper edge of-the band 15 and within the same. The base or free end of the tapered part 19 is preferably of the'same size as that of the post 18 at the outer end or edge of the band 15, that is to say, said base as well as the post, is of a suflicient size to pass through the band, yet so that the body portion of the post, when in position within the band, will contact therewith, thereby forming a bearing or support at such point; a I

The post 18 is provided with one or more grooves 21 which extend longitudinally from the shoulder 20 to a point outwardly from the outer edge or end of the band, as will be readily understood by reference to Fig. 1 of the drawing, and said grooves as well as the grooves 17 in the interior of the band 15, are for the purpose of permitting air to pass out when the post is insertedin the band and cavity 18, and also for the purpose of permitting the cement to enter sa d grooves, and thereby form looks or,

means for more securely holding the post in position.

The grooves 21 in the post 18 correspond in number and location thereon so that when the post is inserted in the band 15 and cavity 18 the grooves 17 in the band will register with the grooves 21 in the post.

So far, the construction of the parts in thcpresent application are substantially the same as those shown and described in my above named Letters Patent, except, that in thepresent instance or constructioinl employ a narrow band 15 instead of a tapered tubular shell used in the patented construction. As the band and shellare by preference made of. platinum whichis quite expensive, it is apparent that by employing theband instead of the shell, considerable saving in said material is attained, yet a very secure and effective support or hearing for the crown-post is provided.

In the construction of the present applica tion, the tooth crown 12 is provided in its upper portion or that part thereof adj acent to the solder-base 11 when the crown. is mounted on the crown-post with one or more. grooves 23 which will lead from the upper ends of the grooves 17 in the band 15 to the frontand rear surfaces of thetoothcrown, as is clearly shown in Figs. 1j and 6 of the drawing. The inner ends of these grooves also communicate with the upper ends of the grooves 21 as shown, and will thus provide escapewaysor passages for air and surplus cement, which will be forced out of the cavity of the tooth crown when the same isfitted on the crown-posh,

y reference to Figs. 1 and'6 it will be seen that one of the grooves 23 extends over the upper portion of the shank or flange 1 1, of the tooth crown while the other groove 23 extends in theopposite direction tothe inner edge of the crown. It will be under stood that the tooth crown may be provided with grooves 23 to correspond in. number,

grooves 23 with those of the band and post and above described will be attained and for the same purpose. 1

A further novel feature of my present invention is the formation on the upper por- 7 tion of the tooth crown with a substantially annular reduced portion 24 and a similar shoulder 25 below the same. By this con struction, it is obvious that when the crowns 12 are placed side by side and it is desired to unite them together by a suitable backing and solder that the upwardly rounded reduced portions 24; of the crowns will be located at. a sufficient distance apart to permit of sufficient amount of solder to be lo cated on the backing which lies on the shoulder 25 as well as the portion 24 and between said rounded portions to greatly strengthen the uniting support or backing for the crowns without interfering with the proper of the crowns in their proper places. l/Vhile I have shown the post 18 provlded fitting with grooves 21 and while I prefer to use a post provided with one or more of such grooves, yet it is obvious that the same may be omitted from the post, when it is apparent that the grooves 23 in the tooth crown will communicate with the grooves 17 in the band 15 and thus permit the escapement of air and surplus cement from the cavity out through the surfaces of the crown. It is also apparent that a post provided with one or more grooves may be employed and the grooves 17 omitted from the band, in which case the inner ends of the grooves 23 in the tooth crown will communicate with the cavity 18 throu h the grooves of the post and thus provide escape-ways to the outer surfaces of the tooth crown.

In carrying my invention into practice, it will be understood that the root 7, is provided with a suitable opening for the reception and retention of the solder-post 9, and a suflicient quantity of cement 8, to secure said post in position in said opening at the time desired. The solder post 9, and backing 10, are secured together as a unit, so that the said post can be readily inserted in the opening in the root 7 therefor, and so that the backing 10, can be easily fitted on the exposed end of the root.

The backing 26 is burnished on the crown 12 and the crown post 18 is extended through a suitable opening in the backing 26, into thecavity 18' of the crown and said backing and post and are soldered together. The parts are now ready to be. fitted, and this is accomplished by placing the post 9 in the opening of the root so that the backing 10 will rest on the exposed end of the root. The

crown 12, backing 26 and post 18 are adjusted in place in the mouth, withwax between the bases 10 and 26. Thenthe post 9, backing 10, post 18, backing 26, (with wax between'it and the backing 10), the crown 12 in place on the backing 26 is removed from the mouth as a unit. Thecrown is then re moved, and the said united parts are invested and the wax removed and supplanted with solder, forming the base 11. That portion of the backing 26 located in the grooves 23 of the crown is removed by any suitable instrument so as to'leave said grooves open. The backing 26 carrying the post 13 is then soldered to the solder-base or root covering,

when a quantity of cement is placed in said cavity, and the crown is then placed on the bacln'ng 26 in which, operation the tapered portion of the post will enter the cavity of the crown, thus causing the cement to surround the tapered portion of the post, where it will become hardened or set, and will firmly hold the crown in position on the post. In the act of placing the crown on its post, it is apparent that the grooves 17 in the band and the grooves 21 in the post, when both are used or when either is used, will permit the air and surplus cement toescape from the cavity of the crown and to pass out through the passageways 23 and thus allow the post to be properly fitted therein. These grooves will also receive a portion of the cement, and after it becomes hardened, it will serve to prevent the crown turning on the post, and otherwise more securely hold it in position. As the bandis provided with one or more of the protuberances 16 on its periphery, it is manifest that the same will be imbedded in the n'iaterial of which crown is made and in which it has been molded, thus preventing any possibility of: rotary movement of the band with respect to its crown.

Having thus fully described my invention, what I claim as new and desire to secure by Letters Patent is- 1. As an article of manufacture, an artificial tooth crown having a post receiving cavity therein and provided with at least one groove in its surface adjacent to the outer end of said cavity, said groove leading from the cavity to the outer surface of the crown, and a metallic band located in the outer extremity of the cavity.

2. As an improved article of manufacture, an artificial tooth crown having a post receiving inwardly enlarged tapered cavity therein and provided with at least one 130 the team

groove in its surface adjacent. to the outer end of said cavity, said groove leading from the cavity to the outer surface of the crown, and a metallic band locatedv in said, cavity and having in its inner surface one or more grooves to register with the groove or grooves of the crown.

3. The combination with a tooth crown having a post receiving inwardly enlarged tapered cavity therein and provided with at least one groove in its surface adjacent to the outer end of: said cavity, said groove leading from the cavity to the outer surface ister with the groove or grooves of the crown.

4. The combination with a tooth crown having a post receiving inwardly enlarged,

tapered cavity therein and provided with one or more grooves in its surface ad acent to the outer end of said cavity, said groove or grooves leading from-the cavity to the outer surface of the crown, the crown also having a reduced andfsubstantlally annular;

portion and a substantially annular shoulder around the outer extremity of said cavity through which said grooves are extended a metallic band located in the outer extremity of the cavity against the walls thereof and;

having in its inner surface one or more longitudinally extending grooves. registering with the grooves of the crown, a securing post located at one of its, ends in the band and having a portion within the, cavity tapered from its inner end towards the innen end of the band;

5. As an improved article of manufacture, a tooth crown having a post receiving cavity therein and provided with one or more grooves in its surface adjacent tothe endof.

said cavity, said groove or grooves leading from the cavity to the outer surface of the crown, the crown also having a reduced and;

substantially annular, portion and aisubstane tiall'y annular shoulderaround the outer. ex-' trcmlty of said cavity through which said grooves are extended, and, a metallic band located in the outer extremity of the cavity. against the walls thereof.

6. In, a device of the base, a tooth crown adapted, to fit. snugly upon said base, the abutting facesof said.

base and crown having. groovesregistering with each other and disposed substantially from side to side of' the crown, and aplocking element in the said grooves.

7. In a, device of the classdescribed, a

pair of closely fitting tooth forming, ele-v ments, one of said'elements having a recess therein, a post on the other element adapted to fit in said recess,,thc abutting faces; of said elements. having grooves therein ex.- tending at their inner ends to and communicating with the said recess, and the said recess and. grooves adapted, to contain a cement. E NOCHVM. EREDERICKS'.

class described, a. 

